2ro
c78d7b0e60
Measured (30 cold trials at the gateway-race commit): the worst cold-start outliers (51s, 72s) were dominated by DEAD-EXIT condemnation cost, not the gateway. A fresh tunnel on a blackholing exit burned probe_fresh's doubled patient budget (2 calls x 2 rounds x 8s ~= 32s) before reselecting. Split the liveness probe into two budgets over a shared probe_with_budget: - probe() (established tunnels: watchdog keepalive + condemnation checks): UNCHANGED - 8s x 2 rounds, worst 16s, same patience as before. - probe_fresh() (gating a just-built tunnel before publish): 5s x 2 rounds x 1 call = 10s worst. 5s is 4.2x the measured worst healthy probe (successful probes: min 465ms / median 774ms / max 1197ms across 15 trials), so the build130 false-condemn regression stays far away. DEAD-EXIT declaration drops from ~36s measured to ~13-17s total; the warn now logs the isolated probe_ms. Also adds the gateway-race observability the verification flagged (race START / WON-by-draw + ms / loser reaped-connected vs dropped-pending / survivor-after-error), so the race is visible in [timing] logs instead of inferred statistically. Verify on the next emulator pass: DEAD EXIT probe_ms <= ~10s, zero false DEAD EXIT across ~15 cold trials, established keepalive/condemn cadence unchanged.
Goblin
Goblin is a private, pay-by-username wallet for GRIN ツ — confidential digital cash on Mimblewimble, with no amounts or addresses on the chain.
Instead of passing slatepack files back and forth, you pay a username (or an npub) and the payment is delivered for you as an end-to-end encrypted message over nostr, routed through the Nym mixnet. Relays only ever see ciphertext — never the amount, the sender, or the recipient — and the mixnet hides who is talking to whom at the network layer.
Goblin is a fork of the Grim egui GRIN wallet: it keeps Grim's full GRIN node/wallet engine and layers a Nostr-native, mobile-first payments experience on top.
What it does
- Send to people — pay a
usernameornpub; the GRIN slatepack travels as a NIP-17 gift-wrapped DM (kind 1059) over the Nym mixnet and is applied automatically by the recipient's wallet. No files to swap, no need to both be online at once. - Manual slatepacks too — when you need to pay or get paid without a handle, Settings → Wallet → Slatepacks exposes the classic by-hand flow: create a slatepack to send, or paste one to receive, finalize, or pay.
- In-app identity — a nostr payment key that is deliberately not part of your seed, so you can rotate it any time to stay unlinkable without touching your funds. An optional human-readable
namecomes from the goblin.st identity service. - Private by construction — GRIN's address-less, confidential chain; your payments and identity (nostr relays, NIP-05 lookups, price) are routed through the Nym mixnet, so who-pays-whom never touches the clear net. The GRIN node connection — block sync and broadcasting your transaction — is direct: public chain data, the same for everyone, and not tied to your identity. Keys, names and history stay on your device.
- Configurable amount pairing — show balances against a world currency, Bitcoin, or sats (rates fetched over the mixnet), or turn the preview off.
- Cross-platform — Linux, macOS, Windows, Android, built in pure Rust on egui.
How a payment travels
you ──slatepack──▶ NIP-17 gift wrap (kind 1059, NIP-44 encrypted)
│
Nym mixnet (5-hop)
│
┌─────────────┴─────────────┐
your relays recipient's DM relays (kind 10050)
└─────────────┬─────────────┘
▼
recipient ◀──unwrap, verify seal author, apply slatepack
The wrap is NIP-44-encrypted, and delivery uses the recipient's DM relay list (kind 10050).
Both parties only need one relay in common. The default set is the Goblin relay plus large public relays (relay.damus.io, nos.lol), and the set is editable in Settings → Relays.
Build
Desktop (Linux / macOS / Windows)
Goblin links the Nym mixnet SDK in-process — the wallet is a single self-contained binary, no sidecar. The SDK builds from a sibling ../nym checkout (a pinned nym tree with a small Android TLS patch):
git clone --branch goblin https://git.us-ea.st/GRIN/nym ../nym
git submodule update --init --recursive
cargo build --release
./target/release/goblin
Goblin's identity and payment traffic — nostr relays, NIP-05 lookups and price fetches — is routed over the mixnet through a network requester (the default is baked into NETWORK_REQUESTER in src/nym/sidecar.rs); the SDK's SOCKS5 listener is run in-process on 127.0.0.1:1080. If something is already listening there, Goblin reuses it. The GRIN node connection (block sync and transaction broadcast) is not mixed — it connects directly, as it carries only public chain data that isn't linked to your wallet.
Android
Install the Android SDK / NDK, then from the repo root:
./scripts/android.sh build|release v7|v8|x86
v7/v8/x86 is the device CPU architecture for build; for release pass a version in major.minor.patch form.
Identity service (goblin-nip05d)
The optional name service lives in goblin-nip05d/ (axum + SQLite) and is deployed at goblin.st. It implements NIP-05 resolution, NIP-98-authenticated registration and release (names are never transferred — on a key rotation you release the old name and re-register, or import your existing identity). The wallet is fully usable — and fully anonymous — without it. Avatars aren't stored or served — clients render them from the pubkey (an npub gradient with the username's first letter, else the Grin mark).
License
Apache License v2.0.
Credits
🤖 Built with AI pair-programming assistance (Claude)
The underlying cross-platform GRIN wallet engine is the upstream Grim project.